shithub: libvpx

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Take out assertion from inverse transforms

Separate the rounding and right shift operations of forward transform
from those of inverse transform. Take out the assertion check from
inverse transforms. If the transform coefficients were constructed to
cause intermediate steps of inverse transform overflow, the codec will
just let it overflow without breaking the decoding flow.

Change-Id: I73cfc3706c4e840fc543a77cbc4cdb0b05d07730

--- a/vp9/common/vp9_idct.h

+++ b/vp9/common/vp9_idct.h

@@ -77,8 +77,7 @@

 static INLINE int dct_const_round_shift(int input) {

   int rv = ROUND_POWER_OF_TWO(input, DCT_CONST_BITS);

-  assert(INT16_MIN <= rv && rv <= INT16_MAX);

-  return rv;

+  return (int16_t)rv;

 }

 typedef void (*transform_1d)(const int16_t*, int16_t*);

--- a/vp9/encoder/vp9_dct.c

+++ b/vp9/encoder/vp9_dct.c

@@ -20,6 +20,12 @@

 #include "vp9/encoder/vp9_dct.h"

+static INLINE int fdct_round_shift(int input) {

+  int rv = ROUND_POWER_OF_TWO(input, DCT_CONST_BITS);

+  assert(INT16_MIN <= rv && rv <= INT16_MAX);

+  return rv;

+}

+

 static void fdct4(const int16_t *input, int16_t *output) {

   int16_t step[4];

   int temp1, temp2;

@@ -31,12 +37,12 @@

   temp1 = (step[0] + step[1]) * cospi_16_64;

   temp2 = (step[0] - step[1]) * cospi_16_64;

-  output[0] = dct_const_round_shift(temp1);

-  output[2] = dct_const_round_shift(temp2);

+  output[0] = fdct_round_shift(temp1);

+  output[2] = fdct_round_shift(temp2);

   temp1 = step[2] * cospi_24_64 + step[3] * cospi_8_64;

   temp2 = -step[2] * cospi_8_64 + step[3] * cospi_24_64;

-  output[1] = dct_const_round_shift(temp1);

-  output[3] = dct_const_round_shift(temp2);

+  output[1] = fdct_round_shift(temp1);

+  output[3] = fdct_round_shift(temp2);

 }

 void vp9_fdct4x4_c(const int16_t *input, int16_t *output, int stride) {

@@ -80,12 +86,12 @@

       step[3] = input[0] - input[3];

       temp1 = (step[0] + step[1]) * cospi_16_64;

       temp2 = (step[0] - step[1]) * cospi_16_64;

-      out[0] = dct_const_round_shift(temp1);

-      out[2] = dct_const_round_shift(temp2);

+      out[0] = fdct_round_shift(temp1);

+      out[2] = fdct_round_shift(temp2);

       temp1 = step[2] * cospi_24_64 + step[3] * cospi_8_64;

       temp2 = -step[2] * cospi_8_64 + step[3] * cospi_24_64;

-      out[1] = dct_const_round_shift(temp1);

-      out[3] = dct_const_round_shift(temp2);

+      out[1] = fdct_round_shift(temp1);

+      out[3] = fdct_round_shift(temp2);

       // Do next column (which is a transposed row in second/horizontal pass)

       in++;

       out += 4;

@@ -138,10 +144,10 @@

   s3 = x2 - x0 + x3;

   // 1-D transform scaling factor is sqrt(2).

-  output[0] = dct_const_round_shift(s0);

-  output[1] = dct_const_round_shift(s1);

-  output[2] = dct_const_round_shift(s2);

-  output[3] = dct_const_round_shift(s3);

+  output[0] = fdct_round_shift(s0);

+  output[1] = fdct_round_shift(s1);

+  output[2] = fdct_round_shift(s2);

+  output[3] = fdct_round_shift(s3);

 }

 static const transform_2d FHT_4[] = {

@@ -204,16 +210,16 @@

   t1 = (x0 - x1) * cospi_16_64;

   t2 =  x2 * cospi_24_64 + x3 *  cospi_8_64;

   t3 = -x2 * cospi_8_64  + x3 * cospi_24_64;

-  output[0] = dct_const_round_shift(t0);

-  output[2] = dct_const_round_shift(t2);

-  output[4] = dct_const_round_shift(t1);

-  output[6] = dct_const_round_shift(t3);

+  output[0] = fdct_round_shift(t0);

+  output[2] = fdct_round_shift(t2);

+  output[4] = fdct_round_shift(t1);

+  output[6] = fdct_round_shift(t3);

   // Stage 2

   t0 = (s6 - s5) * cospi_16_64;

   t1 = (s6 + s5) * cospi_16_64;

-  t2 = dct_const_round_shift(t0);

-  t3 = dct_const_round_shift(t1);

+  t2 = fdct_round_shift(t0);

+  t3 = fdct_round_shift(t1);

   // Stage 3

   x0 = s4 + t2;

@@ -226,10 +232,10 @@

   t1 = x1 * cospi_12_64 + x2 *  cospi_20_64;

   t2 = x2 * cospi_12_64 + x1 * -cospi_20_64;

   t3 = x3 * cospi_28_64 + x0 *  -cospi_4_64;

-  output[1] = dct_const_round_shift(t0);

-  output[3] = dct_const_round_shift(t2);

-  output[5] = dct_const_round_shift(t1);

-  output[7] = dct_const_round_shift(t3);

+  output[1] = fdct_round_shift(t0);

+  output[3] = fdct_round_shift(t2);

+  output[5] = fdct_round_shift(t1);

+  output[7] = fdct_round_shift(t3);

 }

 void vp9_fdct8x8_c(const int16_t *input, int16_t *final_output, int stride) {

@@ -264,16 +270,16 @@

       t1 = (x0 - x1) * cospi_16_64;

       t2 =  x2 * cospi_24_64 + x3 *  cospi_8_64;

       t3 = -x2 * cospi_8_64  + x3 * cospi_24_64;

-      output[0 * 8] = dct_const_round_shift(t0);

-      output[2 * 8] = dct_const_round_shift(t2);

-      output[4 * 8] = dct_const_round_shift(t1);

-      output[6 * 8] = dct_const_round_shift(t3);

+      output[0 * 8] = fdct_round_shift(t0);

+      output[2 * 8] = fdct_round_shift(t2);

+      output[4 * 8] = fdct_round_shift(t1);

+      output[6 * 8] = fdct_round_shift(t3);

       // Stage 2

       t0 = (s6 - s5) * cospi_16_64;

       t1 = (s6 + s5) * cospi_16_64;

-      t2 = dct_const_round_shift(t0);

-      t3 = dct_const_round_shift(t1);

+      t2 = fdct_round_shift(t0);

+      t3 = fdct_round_shift(t1);

       // Stage 3

       x0 = s4 + t2;

@@ -286,10 +292,10 @@

       t1 = x1 * cospi_12_64 + x2 *  cospi_20_64;

       t2 = x2 * cospi_12_64 + x1 * -cospi_20_64;

       t3 = x3 * cospi_28_64 + x0 *  -cospi_4_64;

-      output[1 * 8] = dct_const_round_shift(t0);

-      output[3 * 8] = dct_const_round_shift(t2);

-      output[5 * 8] = dct_const_round_shift(t1);

-      output[7 * 8] = dct_const_round_shift(t3);

+      output[1 * 8] = fdct_round_shift(t0);

+      output[3 * 8] = fdct_round_shift(t2);

+      output[5 * 8] = fdct_round_shift(t1);

+      output[7 * 8] = fdct_round_shift(t3);

       input++;

       output++;

     }

@@ -388,16 +394,16 @@

         t1 = (x0 - x1) * cospi_16_64;

         t2 = x3 * cospi_8_64  + x2 * cospi_24_64;

         t3 = x3 * cospi_24_64 - x2 * cospi_8_64;

-        out[0] = dct_const_round_shift(t0);

-        out[4] = dct_const_round_shift(t2);

-        out[8] = dct_const_round_shift(t1);

-        out[12] = dct_const_round_shift(t3);

+        out[0] = fdct_round_shift(t0);

+        out[4] = fdct_round_shift(t2);

+        out[8] = fdct_round_shift(t1);

+        out[12] = fdct_round_shift(t3);

         // Stage 2

         t0 = (s6 - s5) * cospi_16_64;

         t1 = (s6 + s5) * cospi_16_64;

-        t2 = dct_const_round_shift(t0);

-        t3 = dct_const_round_shift(t1);

+        t2 = fdct_round_shift(t0);

+        t3 = fdct_round_shift(t1);

         // Stage 3

         x0 = s4 + t2;

@@ -410,10 +416,10 @@

         t1 = x1 * cospi_12_64 + x2 *  cospi_20_64;

         t2 = x2 * cospi_12_64 + x1 * -cospi_20_64;

         t3 = x3 * cospi_28_64 + x0 *  -cospi_4_64;

-        out[2] = dct_const_round_shift(t0);

-        out[6] = dct_const_round_shift(t2);

-        out[10] = dct_const_round_shift(t1);

-        out[14] = dct_const_round_shift(t3);

+        out[2] = fdct_round_shift(t0);

+        out[6] = fdct_round_shift(t2);

+        out[10] = fdct_round_shift(t1);

+        out[14] = fdct_round_shift(t3);

       }

       // Work on the next eight values; step1 -> odd_results

       {

@@ -420,12 +426,12 @@

         // step 2

         temp1 = (step1[5] - step1[2]) * cospi_16_64;

         temp2 = (step1[4] - step1[3]) * cospi_16_64;

-        step2[2] = dct_const_round_shift(temp1);

-        step2[3] = dct_const_round_shift(temp2);

+        step2[2] = fdct_round_shift(temp1);

+        step2[3] = fdct_round_shift(temp2);

         temp1 = (step1[4] + step1[3]) * cospi_16_64;

         temp2 = (step1[5] + step1[2]) * cospi_16_64;

-        step2[4] = dct_const_round_shift(temp1);

-        step2[5] = dct_const_round_shift(temp2);

+        step2[4] = fdct_round_shift(temp1);

+        step2[5] = fdct_round_shift(temp2);

         // step 3

         step3[0] = step1[0] + step2[3];

         step3[1] = step1[1] + step2[2];

@@ -438,12 +444,12 @@

         // step 4

         temp1 = step3[1] *  -cospi_8_64 + step3[6] * cospi_24_64;

         temp2 = step3[2] * -cospi_24_64 - step3[5] *  cospi_8_64;

-        step2[1] = dct_const_round_shift(temp1);

-        step2[2] = dct_const_round_shift(temp2);

+        step2[1] = fdct_round_shift(temp1);

+        step2[2] = fdct_round_shift(temp2);

         temp1 = step3[2] * -cospi_8_64 + step3[5] * cospi_24_64;

         temp2 = step3[1] * cospi_24_64 + step3[6] *  cospi_8_64;

-        step2[5] = dct_const_round_shift(temp1);

-        step2[6] = dct_const_round_shift(temp2);

+        step2[5] = fdct_round_shift(temp1);

+        step2[6] = fdct_round_shift(temp2);

         // step 5

         step1[0] = step3[0] + step2[1];

         step1[1] = step3[0] - step2[1];

@@ -456,20 +462,20 @@

         // step 6

         temp1 = step1[0] * cospi_30_64 + step1[7] *  cospi_2_64;

         temp2 = step1[1] * cospi_14_64 + step1[6] * cospi_18_64;

-        out[1] = dct_const_round_shift(temp1);

-        out[9] = dct_const_round_shift(temp2);

+        out[1] = fdct_round_shift(temp1);

+        out[9] = fdct_round_shift(temp2);

         temp1 = step1[2] * cospi_22_64 + step1[5] * cospi_10_64;

         temp2 = step1[3] *  cospi_6_64 + step1[4] * cospi_26_64;

-        out[5] = dct_const_round_shift(temp1);

-        out[13] = dct_const_round_shift(temp2);

+        out[5] = fdct_round_shift(temp1);

+        out[13] = fdct_round_shift(temp2);

         temp1 = step1[3] * -cospi_26_64 + step1[4] *  cospi_6_64;

         temp2 = step1[2] * -cospi_10_64 + step1[5] * cospi_22_64;

-        out[3] = dct_const_round_shift(temp1);

-        out[11] = dct_const_round_shift(temp2);

+        out[3] = fdct_round_shift(temp1);

+        out[11] = fdct_round_shift(temp2);

         temp1 = step1[1] * -cospi_18_64 + step1[6] * cospi_14_64;

         temp2 = step1[0] *  -cospi_2_64 + step1[7] * cospi_30_64;

-        out[7] = dct_const_round_shift(temp1);

-        out[15] = dct_const_round_shift(temp2);

+        out[7] = fdct_round_shift(temp1);

+        out[15] = fdct_round_shift(temp2);

       }

       // Do next column (which is a transposed row in second/horizontal pass)

       in++;

@@ -503,14 +509,14 @@

   s6 = cospi_26_64 * x6 + cospi_6_64  * x7;

   s7 = cospi_6_64  * x6 - cospi_26_64 * x7;

-  x0 = dct_const_round_shift(s0 + s4);

-  x1 = dct_const_round_shift(s1 + s5);

-  x2 = dct_const_round_shift(s2 + s6);

-  x3 = dct_const_round_shift(s3 + s7);

-  x4 = dct_const_round_shift(s0 - s4);

-  x5 = dct_const_round_shift(s1 - s5);

-  x6 = dct_const_round_shift(s2 - s6);

-  x7 = dct_const_round_shift(s3 - s7);

+  x0 = fdct_round_shift(s0 + s4);

+  x1 = fdct_round_shift(s1 + s5);

+  x2 = fdct_round_shift(s2 + s6);

+  x3 = fdct_round_shift(s3 + s7);

+  x4 = fdct_round_shift(s0 - s4);

+  x5 = fdct_round_shift(s1 - s5);

+  x6 = fdct_round_shift(s2 - s6);

+  x7 = fdct_round_shift(s3 - s7);

   // stage 2

   s0 = x0;

@@ -526,10 +532,10 @@

   x1 = s1 + s3;

   x2 = s0 - s2;

   x3 = s1 - s3;

-  x4 = dct_const_round_shift(s4 + s6);

-  x5 = dct_const_round_shift(s5 + s7);

-  x6 = dct_const_round_shift(s4 - s6);

-  x7 = dct_const_round_shift(s5 - s7);

+  x4 = fdct_round_shift(s4 + s6);

+  x5 = fdct_round_shift(s5 + s7);

+  x6 = fdct_round_shift(s4 - s6);

+  x7 = fdct_round_shift(s5 - s7);

   // stage 3

   s2 = cospi_16_64 * (x2 + x3);

@@ -537,10 +543,10 @@

   s6 = cospi_16_64 * (x6 + x7);

   s7 = cospi_16_64 * (x6 - x7);

-  x2 = dct_const_round_shift(s2);

-  x3 = dct_const_round_shift(s3);

-  x6 = dct_const_round_shift(s6);

-  x7 = dct_const_round_shift(s7);

+  x2 = fdct_round_shift(s2);

+  x3 = fdct_round_shift(s3);

+  x6 = fdct_round_shift(s6);

+  x7 = fdct_round_shift(s7);

   output[0] =   x0;

   output[1] = - x4;

@@ -693,16 +699,16 @@

     t1 = (x0 - x1) * cospi_16_64;

     t2 = x3 * cospi_8_64  + x2 * cospi_24_64;

     t3 = x3 * cospi_24_64 - x2 * cospi_8_64;

-    out[0] = dct_const_round_shift(t0);

-    out[4] = dct_const_round_shift(t2);

-    out[8] = dct_const_round_shift(t1);

-    out[12] = dct_const_round_shift(t3);

+    out[0] = fdct_round_shift(t0);

+    out[4] = fdct_round_shift(t2);

+    out[8] = fdct_round_shift(t1);

+    out[12] = fdct_round_shift(t3);

     // Stage 2

     t0 = (s6 - s5) * cospi_16_64;

     t1 = (s6 + s5) * cospi_16_64;

-    t2 = dct_const_round_shift(t0);

-    t3 = dct_const_round_shift(t1);

+    t2 = fdct_round_shift(t0);

+    t3 = fdct_round_shift(t1);

     // Stage 3

     x0 = s4 + t2;

@@ -715,21 +721,21 @@

     t1 = x1 * cospi_12_64 + x2 *  cospi_20_64;

     t2 = x2 * cospi_12_64 + x1 * -cospi_20_64;

     t3 = x3 * cospi_28_64 + x0 *  -cospi_4_64;

-    out[2] = dct_const_round_shift(t0);

-    out[6] = dct_const_round_shift(t2);

-    out[10] = dct_const_round_shift(t1);

-    out[14] = dct_const_round_shift(t3);

+    out[2] = fdct_round_shift(t0);

+    out[6] = fdct_round_shift(t2);

+    out[10] = fdct_round_shift(t1);

+    out[14] = fdct_round_shift(t3);

   }

   // step 2

   temp1 = (step1[5] - step1[2]) * cospi_16_64;

   temp2 = (step1[4] - step1[3]) * cospi_16_64;

-  step2[2] = dct_const_round_shift(temp1);

-  step2[3] = dct_const_round_shift(temp2);

+  step2[2] = fdct_round_shift(temp1);

+  step2[3] = fdct_round_shift(temp2);

   temp1 = (step1[4] + step1[3]) * cospi_16_64;

   temp2 = (step1[5] + step1[2]) * cospi_16_64;

-  step2[4] = dct_const_round_shift(temp1);

-  step2[5] = dct_const_round_shift(temp2);

+  step2[4] = fdct_round_shift(temp1);

+  step2[5] = fdct_round_shift(temp2);

   // step 3

   step3[0] = step1[0] + step2[3];

@@ -744,12 +750,12 @@

   // step 4

   temp1 = step3[1] *  -cospi_8_64 + step3[6] * cospi_24_64;

   temp2 = step3[2] * -cospi_24_64 - step3[5] *  cospi_8_64;

-  step2[1] = dct_const_round_shift(temp1);

-  step2[2] = dct_const_round_shift(temp2);

+  step2[1] = fdct_round_shift(temp1);

+  step2[2] = fdct_round_shift(temp2);

   temp1 = step3[2] * -cospi_8_64 + step3[5] * cospi_24_64;

   temp2 = step3[1] * cospi_24_64 + step3[6] *  cospi_8_64;

-  step2[5] = dct_const_round_shift(temp1);

-  step2[6] = dct_const_round_shift(temp2);

+  step2[5] = fdct_round_shift(temp1);

+  step2[6] = fdct_round_shift(temp2);

   // step 5

   step1[0] = step3[0] + step2[1];

@@ -764,23 +770,23 @@

   // step 6

   temp1 = step1[0] * cospi_30_64 + step1[7] *  cospi_2_64;

   temp2 = step1[1] * cospi_14_64 + step1[6] * cospi_18_64;

-  out[1] = dct_const_round_shift(temp1);

-  out[9] = dct_const_round_shift(temp2);

+  out[1] = fdct_round_shift(temp1);

+  out[9] = fdct_round_shift(temp2);

   temp1 = step1[2] * cospi_22_64 + step1[5] * cospi_10_64;

   temp2 = step1[3] *  cospi_6_64 + step1[4] * cospi_26_64;

-  out[5] = dct_const_round_shift(temp1);

-  out[13] = dct_const_round_shift(temp2);

+  out[5] = fdct_round_shift(temp1);

+  out[13] = fdct_round_shift(temp2);

   temp1 = step1[3] * -cospi_26_64 + step1[4] *  cospi_6_64;

   temp2 = step1[2] * -cospi_10_64 + step1[5] * cospi_22_64;

-  out[3] = dct_const_round_shift(temp1);

-  out[11] = dct_const_round_shift(temp2);

+  out[3] = fdct_round_shift(temp1);

+  out[11] = fdct_round_shift(temp2);

   temp1 = step1[1] * -cospi_18_64 + step1[6] * cospi_14_64;

   temp2 = step1[0] *  -cospi_2_64 + step1[7] * cospi_30_64;

-  out[7] = dct_const_round_shift(temp1);

-  out[15] = dct_const_round_shift(temp2);

+  out[7] = fdct_round_shift(temp1);

+  out[15] = fdct_round_shift(temp2);

 }

 static void fadst16(const int16_t *input, int16_t *output) {

@@ -821,22 +827,22 @@

   s14 = x14 * cospi_29_64 + x15 * cospi_3_64;

   s15 = x14 * cospi_3_64  - x15 * cospi_29_64;

-  x0 = dct_const_round_shift(s0 + s8);

-  x1 = dct_const_round_shift(s1 + s9);

-  x2 = dct_const_round_shift(s2 + s10);

-  x3 = dct_const_round_shift(s3 + s11);

-  x4 = dct_const_round_shift(s4 + s12);

-  x5 = dct_const_round_shift(s5 + s13);

-  x6 = dct_const_round_shift(s6 + s14);

-  x7 = dct_const_round_shift(s7 + s15);

-  x8  = dct_const_round_shift(s0 - s8);

-  x9  = dct_const_round_shift(s1 - s9);

-  x10 = dct_const_round_shift(s2 - s10);

-  x11 = dct_const_round_shift(s3 - s11);

-  x12 = dct_const_round_shift(s4 - s12);

-  x13 = dct_const_round_shift(s5 - s13);

-  x14 = dct_const_round_shift(s6 - s14);

-  x15 = dct_const_round_shift(s7 - s15);

+  x0 = fdct_round_shift(s0 + s8);

+  x1 = fdct_round_shift(s1 + s9);

+  x2 = fdct_round_shift(s2 + s10);

+  x3 = fdct_round_shift(s3 + s11);

+  x4 = fdct_round_shift(s4 + s12);

+  x5 = fdct_round_shift(s5 + s13);

+  x6 = fdct_round_shift(s6 + s14);

+  x7 = fdct_round_shift(s7 + s15);

+  x8  = fdct_round_shift(s0 - s8);

+  x9  = fdct_round_shift(s1 - s9);

+  x10 = fdct_round_shift(s2 - s10);

+  x11 = fdct_round_shift(s3 - s11);

+  x12 = fdct_round_shift(s4 - s12);

+  x13 = fdct_round_shift(s5 - s13);

+  x14 = fdct_round_shift(s6 - s14);

+  x15 = fdct_round_shift(s7 - s15);

   // stage 2

   s0 = x0;

@@ -864,14 +870,14 @@

   x5 = s1 - s5;

   x6 = s2 - s6;

   x7 = s3 - s7;

-  x8 = dct_const_round_shift(s8 + s12);

-  x9 = dct_const_round_shift(s9 + s13);

-  x10 = dct_const_round_shift(s10 + s14);

-  x11 = dct_const_round_shift(s11 + s15);

-  x12 = dct_const_round_shift(s8 - s12);

-  x13 = dct_const_round_shift(s9 - s13);

-  x14 = dct_const_round_shift(s10 - s14);

-  x15 = dct_const_round_shift(s11 - s15);

+  x8 = fdct_round_shift(s8 + s12);

+  x9 = fdct_round_shift(s9 + s13);

+  x10 = fdct_round_shift(s10 + s14);

+  x11 = fdct_round_shift(s11 + s15);

+  x12 = fdct_round_shift(s8 - s12);

+  x13 = fdct_round_shift(s9 - s13);

+  x14 = fdct_round_shift(s10 - s14);

+  x15 = fdct_round_shift(s11 - s15);

   // stage 3

   s0 = x0;

@@ -895,18 +901,18 @@

   x1 = s1 + s3;

   x2 = s0 - s2;

   x3 = s1 - s3;

-  x4 = dct_const_round_shift(s4 + s6);

-  x5 = dct_const_round_shift(s5 + s7);

-  x6 = dct_const_round_shift(s4 - s6);

-  x7 = dct_const_round_shift(s5 - s7);

+  x4 = fdct_round_shift(s4 + s6);

+  x5 = fdct_round_shift(s5 + s7);

+  x6 = fdct_round_shift(s4 - s6);

+  x7 = fdct_round_shift(s5 - s7);

   x8 = s8 + s10;

   x9 = s9 + s11;

   x10 = s8 - s10;

   x11 = s9 - s11;

-  x12 = dct_const_round_shift(s12 + s14);

-  x13 = dct_const_round_shift(s13 + s15);

-  x14 = dct_const_round_shift(s12 - s14);

-  x15 = dct_const_round_shift(s13 - s15);

+  x12 = fdct_round_shift(s12 + s14);

+  x13 = fdct_round_shift(s13 + s15);

+  x14 = fdct_round_shift(s12 - s14);

+  x15 = fdct_round_shift(s13 - s15);

   // stage 4

   s2 = (- cospi_16_64) * (x2 + x3);

@@ -918,14 +924,14 @@

   s14 = (- cospi_16_64) * (x14 + x15);

   s15 = cospi_16_64 * (x14 - x15);

-  x2 = dct_const_round_shift(s2);

-  x3 = dct_const_round_shift(s3);

-  x6 = dct_const_round_shift(s6);

-  x7 = dct_const_round_shift(s7);

-  x10 = dct_const_round_shift(s10);

-  x11 = dct_const_round_shift(s11);

-  x14 = dct_const_round_shift(s14);

-  x15 = dct_const_round_shift(s15);

+  x2 = fdct_round_shift(s2);

+  x3 = fdct_round_shift(s3);

+  x6 = fdct_round_shift(s6);

+  x7 = fdct_round_shift(s7);

+  x10 = fdct_round_shift(s10);

+  x11 = fdct_round_shift(s11);

+  x14 = fdct_round_shift(s14);

+  x15 = fdct_round_shift(s15);

   output[0] = x0;

   output[1] = - x8;

-- 

⑨